Linux is such a wonderful kernel for many reasons, but I find its adaptability to be the tops. You can get an operating system based on the kernel running on such a broad range of hardware -- something Microsoft can only dream about with its venerable Windows.
Even though Linux can run on damn-near anything, it is beneficial for developers to have a reference platform to use for creating. Of course, they can always expand from that jumping point. Today, Canonical announces that the Dragonboard 410c hardware will be the reference platform for Ubuntu Core on ARM 64-bit.